DESCRIPTION (Applicant's Abstract): The proposed research is focused on developing a low-cost diagnostic technology to screen for digestive diseases in a clinical setting. The goal is to incorporate screening for multiple diseases into a single test. Our approach is based upon hybridization of DNA to specific peptide nucleic acid (PNA) probes attached to a microcantilever array. By measuring the bending of individual cantilevers induced by hybridization of DNA, mutant and normal alleles of a gene may be identified. The increased stability of PNA/DNA duplexes, compared to that of DNA/DNA, allows monitoring of multiple mutations with a single device. The Phase I work plan is designed to characterize PNA/DNA hybridization on microcantilever arrays by studying the G-to-A transition associated with the disease-causing Cys282Tyr mutation on the HFE gene. In Phase II, large cantilever arrays will be implemented and a prototype instrument will be built to demonstrate the commercial potential of the technology. PROPOSED COMMERCIAL APPLICATIONS: This project is aimed toward developing a low-cost technique for screening genetic diseases. The technology could be utilized for screening of inherited diseases, including the presence of hereditary digestive disease in infants. The technology could also be used for a wide variety of DNA sequence recognition applications, including screening for infectious pathogens in a hospital or as point-of-care in the physician's office, toxic chemicals or radioisotopes in industry or biowarfare, or in veterinary medicine.